Erythema Multiforme

Question 1

Define Erythema Multiforme?

Answer 1

An acute hypersensitivity reaction of the skin and mucous membranes

Question 2

What is Stevens-Johnson Syndrome?

Answer 2

A severe form of Erythema Multiforme with bullous lesions and necrotic ulcers

Question 3

What is the aetiology of Erythema Multiforme?

Answer 3

Degeneration of basal epidermal cells
Development of vesicles between cells in the basement membrane
Lymphocytic infiltrate around the blood vessels and at the dermo-epidermal junction
A precipitating factor is only identified 50% of the time

Question 4

What are the precipitating factors for Erythema Multiforme?

Answer 4

Drugs
Infection
Inflammatory
Malignancy
Radiotherapy

Question 5

What are some examples of drugs that can cause Erythema Multiforme?

Answer 5

Sulphonamides
Penicillin
Phenytoin

Question 6

What are some examples of some infections that can precipitate Erythema Multiforme?

Answer 6

HSV 
EBV
Adenovirus 
Chlamydia 
Histoplasmosis

Question 7

What are some examples of inflammatory causes of Erythema Multiforme?

Answer 7

Rheumatoid arthritids
SLE
Sarcoidosis
Ulcerative Colitis

Question 8

What are some examples of malignancies that can cause Erythema Multiforme?

Answer 8

Lymphomas
Leukaemia
Myeloma

Question 9

What is the epidemiology of Erythema Multiforme?

Answer 9

Any age group
Mainly in CHILDREN and YOUNG ADULTS
TWICE as common in MALES

Question 10

What are the presenting symptoms of Erythema Multiforme?

Answer 10

Non-specific prodromal symptoms of upper respiratory tract infection
Sudden apperance of itching/burning/painful skin lesions
Skin lesions may fade leaving pigmentation

Question 11

What are the signs of Erythema Multiforme on physical examination?

Answer 11

Classic target (bull’s eye) lesions with a rim of erythema surrounding a paler area
Vesicles/bullae
Urticarial plaques
Lesions are often symmetrical and distributed over the arms and legs including the palms, soles and externsor surfaces

Question 12

What is Stevens-Johnson syndrome characterised by?

Answer 12

Affecting > 2 mucous membranes (e.g. conjunctiva, cornea, lips, mouth, genitalia)
Systemic symptoms (e.g.sore throat, cough, fever, headache, myalgia, arthralgia, diarrhoea/vomiting)
Shock (hypotension and tachycardia)

Question 13

What investigations can we do for Erythema Multiforme?

Answer 13

Usually unnecessary - Erythema Multiforme is very much a clinical diagnosis
Bloods
Imaging
Skin Biopsy

Question 14

What bloods would you do for Erythema Multiforme?

Answer 14

High WC
Eosinophils
ESR/CRP

Question 15

Why do we do imaging for Erythema Multiforme?

Answer 15

Exclude sarcoidosis and atypical pneumonia